Split UIGrid.cpp into three files for maintainability, closes #149

UIGrid.cpp (3338 lines) split into:
- UIGrid.cpp (1588 lines): core logic, rendering, init, click handling, cell callbacks
- UIGridPyMethods.cpp (1104 lines): Python method implementations and method tables
- UIGridPyProperties.cpp (597 lines): Python getter/setter implementations and getsetters table

All 277 tests pass with no regressions.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

tools/build_debug_libs.sh

@@ -0,0 +1,138 @@
+#!/usr/bin/env bash
+#
+# Build libtcod-headless with sanitizer instrumentation.
+#
+# Usage:
+#   tools/build_debug_libs.sh              # Build with debug symbols only
+#   tools/build_debug_libs.sh --asan       # Build with AddressSanitizer
+#   tools/build_debug_libs.sh --tsan       # Build with ThreadSanitizer
+#   tools/build_debug_libs.sh --clean      # Remove build artifacts first
+#
+# Output: __lib_debug/libtcod.so (instrumented)
+#
+# Why: The pre-built libtcod in __lib/ is uninstrumented. ASan/TSan can
+# detect bugs in our code that corrupt libtcod's memory, but cannot detect
+# bugs originating inside libtcod (FOV, pathfinding) that touch our data.
+# Building libtcod with the same sanitizer flags closes this gap.
+
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+PROJECT_ROOT="$(cd "$SCRIPT_DIR/.." && pwd)"
+LIBTCOD_DIR="$PROJECT_ROOT/modules/libtcod-headless"
+OUTPUT_DIR="$PROJECT_ROOT/__lib_debug"
+JOBS="$(nproc 2>/dev/null || echo 4)"
+
+MODE="debug"
+CLEAN=0
+for arg in "$@"; do
+    case "$arg" in
+        --asan)  MODE="asan" ;;
+        --tsan)  MODE="tsan" ;;
+        --clean) CLEAN=1 ;;
+        --help|-h)
+            echo "Usage: $0 [--asan|--tsan] [--clean]"
+            echo ""
+            echo "Flags:"
+            echo "  (default)  Debug symbols only (-g -O1)"
+            echo "  --asan     AddressSanitizer + UBSan instrumentation"
+            echo "  --tsan     ThreadSanitizer instrumentation"
+            echo "  --clean    Remove build artifacts before building"
+            exit 0
+            ;;
+        *)
+            echo "Unknown argument: $arg"
+            echo "Run '$0 --help' for usage."
+            exit 1
+            ;;
+    esac
+done
+
+BUILD_DIR="$LIBTCOD_DIR/build-debug-$MODE"
+
+case "$MODE" in
+    debug)
+        SANITIZER_FLAGS=""
+        echo "=== Building libtcod-headless with debug symbols ==="
+        ;;
+    asan)
+        SANITIZER_FLAGS="-fsanitize=address,undefined -fno-omit-frame-pointer"
+        echo "=== Building libtcod-headless with ASan + UBSan ==="
+        ;;
+    tsan)
+        SANITIZER_FLAGS="-fsanitize=thread"
+        echo "=== Building libtcod-headless with TSan ==="
+        ;;
+esac
+
+if [ "$CLEAN" -eq 1 ]; then
+    echo "Cleaning $BUILD_DIR..."
+    rm -rf "$BUILD_DIR"
+fi
+
+if [ ! -f "$LIBTCOD_DIR/CMakeLists.txt" ]; then
+    echo "ERROR: libtcod-headless not found at $LIBTCOD_DIR/CMakeLists.txt"
+    echo "Make sure the submodule is initialized:"
+    echo "  git submodule update --init modules/libtcod-headless"
+    exit 1
+fi
+
+mkdir -p "$BUILD_DIR"
+cd "$BUILD_DIR"
+
+CMAKE_EXTRA_FLAGS=""
+if [ -n "$SANITIZER_FLAGS" ]; then
+    CMAKE_EXTRA_FLAGS="-DCMAKE_C_FLAGS=$SANITIZER_FLAGS -DCMAKE_CXX_FLAGS=$SANITIZER_FLAGS"
+fi
+
+if [ ! -f Makefile ]; then
+    echo "Configuring libtcod-headless ($MODE)..."
+    # shellcheck disable=SC2086
+    cmake "$LIBTCOD_DIR" \
+        -DCMAKE_BUILD_TYPE=Debug \
+        -DBUILD_SHARED_LIBS=ON \
+        $CMAKE_EXTRA_FLAGS
+    echo "Configuration complete."
+else
+    echo "Makefile exists, skipping configure (use --clean to reconfigure)."
+fi
+
+echo "Building libtcod-headless (-j$JOBS)..."
+make -j"$JOBS"
+
+BUILT_LIB=""
+for candidate in "$BUILD_DIR/libtcod.so" "$BUILD_DIR/libtcod"*.so*; do
+    if [ -f "$candidate" ] && [ ! -L "$candidate" ]; then
+        BUILT_LIB="$candidate"
+        break
+    fi
+done
+
+if [ -z "$BUILT_LIB" ]; then
+    echo "ERROR: Could not find built libtcod.so in $BUILD_DIR"
+    echo "Contents:"
+    ls -la "$BUILD_DIR"/libtcod* 2>/dev/null || echo "  (no libtcod files found)"
+    exit 1
+fi
+
+mkdir -p "$OUTPUT_DIR"
+
+BASENAME="$(basename "$BUILT_LIB")"
+echo "Copying $BUILT_LIB -> $OUTPUT_DIR/$BASENAME"
+cp "$BUILT_LIB" "$OUTPUT_DIR/$BASENAME"
+
+cd "$OUTPUT_DIR"
+for link_name in libtcod.so libtcod.so.2 libtcod.so.2.2; do
+    if [ "$link_name" != "$BASENAME" ]; then
+        ln -sf "$BASENAME" "$link_name"
+    fi
+done
+
+echo ""
+echo "=== Instrumented libtcod build complete ==="
+echo "  Mode:    $MODE"
+echo "  Library: $OUTPUT_DIR/$BASENAME"
+echo "  Size:    $(du -h "$OUTPUT_DIR/$BASENAME" | cut -f1)"
+echo ""
+echo "The existing 'make asan' / 'make tsan' targets link __lib_debug/ first,"
+echo "so the instrumented libtcod will be picked up automatically."